Electrical System Checks
WARNING
Disconnect the battery before opening the com-
partment cover or inspecting or repairing the elec-
trical system. If a tool causes a short circuit, the
high current flow from the battery can cause per-
sonal injury or property damage.
The capacitor in the transistor controller can hold
an electrical charge after the battery is disconnec-
ted. To prevent electrical shock and personal in-
jury, discharge the capacitor before inspecting or
repairing any component in the drive unit com-
partment. Wear safety glasses. Make certain the
battery has been disconnected.
All checks, adjustments, and repairs in the drive unit com-
partment are done with the compartment cover removed.
Remove the drive unit compartment cover for access to the
electrical components.
SAFETY PRECAUTIONS
WARNING
Some checks require the battery to be reconnec-
ted. DO NOT connect the battery until the proce-
dure tells you to do so. Make sure the drive wheel
is raised to prevent truck movement and possible
injury. Raise the drive wheel. The blocks must
prevent the lift truck from falling and causing per-
sonal injury or property damage.
CAUTION
To avoid controller damage, always disconnect
the battery before disconnecting any cables from
the controller. Discharge the capacitor, and never
put power to the controller with any power wire
disconnected. Never short any controller terminal
or motor terminal to the battery. Make sure to use
proper procedure when servicing the controller.
1.
Block lift truck so the drive tire is raised slightly off
the floor to prevent unexpected movement when mak-
ing checks.
WARNING
DO NOT put the lift truck on blocks unless the
surface is solid, even, and level. Make sure that all
blocks used to support the lift truck are solid,
one-piece units. Put a block in front and back of
the tire or wheels touching the ground to prevent
unexpected movement of the lift truck.
WARNING
DO NOT raise the lift truck by attaching an over-
head crane to areas that will be damaged. Some
of these points are not designed to support the
weight of the lift truck. The lift truck can be dam-
aged or it can fall, causing serious injury. Attach
the chain or sling to a support structure of the lift
truck frame.
WARNING
Never raise the forks any higher than necessary
to change the load wheels. Always raise both
forks at the same time. Raising the forks too high
or unevenly can cause the lift truck tip over and
cause personal injury or property damage.
2.
Use a crane or jack to raise the forks or motor compart-
ment assembly. Put blocks under the forks or the edge
plates of the motor compartment assembly. See Fig-
ure 5. Make sure the lifting device has a capacity of at
least two-thirds (2/3) of the combined weight of the lift
truck and the battery as listed on the nameplate.
3.
Turn the key switch to the
OFF
position and discon-
nect the battery.
4.
Discharge the capacitors. See Special Precautions in
this section.
NOTE:
These checks require a volt-ohmmeter with a me-
ter movement. Most digital meters will not operate cor-
rectly for some of these checks. Specific checks require ad-
ditional equipment.
NOTE:
The correct meter polarity is necessary for the
checks. The voltage checks are made between the point in-
dicated in Table 1 and battery negative. Connect the meter
negative to battery negative.
NOTE:
The battery does not have to be removed to check
the specific gravity.
5.
Using a hydrometer, check the specific gravity of the
battery. If the specific gravity is less than 1.260, the
battery is not fully charged or is damaged. A fully-
charged battery has a specific gravity of 1.270 to
1.290. A discharged battery has a specific gravity of
approximately 1.165.
Electrical System Checks
2200 SRM 1640
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